Abstract
Pycnogenol (PYC), a standardized extract derived from the bark of the French maritime pine (Pinus pinaster ssp. atlantica), exhibits a broad spectrum of biological activities, including antioxidant, anti-inflammatory, immunomodulatory, antiviral, and anticancer effects. These effects are attributed to the rich profile of polyphenolic compounds, which confer potent antioxidant and anti-inflammatory properties. Viral infections frequently induce oxidative stress, inflammation, and immune dysregulation, thereby posing substantial challenges to global public health. Accordingly, the development of effective antiviral agents applicable across diverse viral outbreak settings remains a critical goal. PYC has demonstrated antioxidant, anti-inflammatory, and antiviral potential against several viruses, including hepatitis C virus, dengue virus, and severe acute respiratory syndrome coronavirus 2. In addition, PYC exhibited anticancer activity by modulating cell signaling pathways, inhibiting tumor cell proliferation, inducing apoptosis, and suppressing angiogenesis. However, further research and clinical validation are required to confirm its therapeutic applications. Accordingly, this review summarizes the current understanding regarding the antioxidant, anti-inflammatory, and anticancer mechanisms of PYC. Moreover, the review highlights its immunomodulatory properties to inform future antiviral and anticancer drug development and therapeutic strategies.